White House spokesman Josh Earnest told reporters: “The allegations for which this individual was arrested and imprisoned would not give rise to arrest or imprisonment in the United States or in just about any other country in the world.

“It is increasingly clear that the North Korean government seeks to use these US citizens as pawns to pursue a political agenda.”

The new sanctions, over North Korea’s recent nuclear and missile testing, include the freezing of North Korean government property in the US and a ban on US exports to North Korea.

Both US and non-US citizens with links to Pyongyang’s economy can also now be blacklisted.

“The US and the global community will not tolerate North Korea’s illicit nuclear and ballistic missile activities, and we will continue to impose costs on North Korea until it comes into compliance with its international obligations,” said Earnest.

Obama imposes more sanctions on North Korea in retaliation for its nuclear and ballistic missile tests. https://t.co/WyKMoMzsjE

The new sanctions considerably expand punitive measures that have already been in force against Pyongyang and are now similar to the comprehensive bans previously imposed on countries such as Iran and Myanmar.

North Korea carried out a fourth nuclear test in January and recently fired short and long-range missiles.

The North Korean leader Kim Jong-un further angered the international community when he said it had developed miniature nuclear warheads that can be placed on its missiles. Many experts doubt the claims are true, however.